In the far Northern reaches, a group of sled dogs gain a much-needed rest from their master. Off in the distance, a hungry polar bear approaches, causing great alarm among the pack and their master. When the bear arrives, the lead dog signals the intent to play, and the bear goes along. Threat averted!

Play is pervasive in the animal kingdom. Yet it’s incredible to think that the desire for play can take precedence over the survival instinct. After all, to the casual observer, play is a seemingly purposeless expenditure of time that provides a pleasant diversion from the ordinary business of life. But the impulse to play is a biological drive. And as Dr. Stuart Brown details in Play: How It Shapes the Brain, Opens the Imagination, and Integrates the Soul, play has been proven scientifically to be an incredibly useful activity.

Our brains self-create as a function of the environments in which they operate and the experiences they amass. Play stimulates secretion of brain-derived neurotropic factors (BDNF) that the brain uses to build and maintain its cellular circuitry. BDNF improves neural function and helps enrich and shape neural connections. Play also helps the brain gain experience in contrived settings that can be deployed in real life circumstances – e.g., practicing karate with friends at a dojo that can be used if and when a physical threat arises. And, of course, play provides a low-risk setting to discover and cultivate all those wonderful skills.

Play optimizes the mind-set to improve alertness, attention, and motivation. Transforming a learning experience from rote memorization to a playful game vastly improves engagement in the moment and retention after the fact. The more experimentation with the “game,” the greater the comprehension of how the subject matter at hand works.

Play confers skills that bolster emotional intelligence. Players learn how to cooperate, how to navigate difference, and how to establish and maintain trust. They also learn how to discern who has their backs and who is gunning for them. Belonging is an outgrowth of social play.

Play is essential for aging gracefully. Studies consistently link favorable health outcomes with adults who continue to explore, play games, and learn throughout their lives. They’re not only less susceptible to dementia, they’re less likely to suffer from heart disease and other ailments seemingly unrelated to the brain.

Play and work are mutually supportive. In both, we learn new things, exercise our creativity, develop our skills, forge relationships, stretch ourselves, and achieve goals. Play helps us cope with work-related stress and personal difficulties while providing a sense of expansiveness that allows for clear thinking. It can provide the space for the critical insight that solves a problem or illuminates an opportunity. And, as Dr. Brown notes, “true play that comes from our own inner needs and desires is the only path to finding lasting joy and satisfaction in our work.”

Most of us like to think that we’re in complete control of our actions. We picture ourselves as rational beings capable of making the right choices at the right times for the right reasons. But as Dr. Jonathan Sapolsky writes in Behave: The Biology of Humans and Our Best and Worst, many factors influence the biology of behavior, some of which operate below conscious awareness.

Sensory input impacts our thought processes. For example, if we’re cradling a warm drink, we think warm thoughts about others. By contrast, cold drinks elicit a more frosty assessment. And if we’re in pain (or even really hungry), we’re more apt to be aggressive.

Rapid response brain regions impact our decisions and behaviors. The amygdala perceives sensory data through the lens of fear, uncertainty, and doubt. It evokes action to keep us from harm’s way and injects distrust and vigilance into decision processes. The hippocampus provides assistance by retaining information related to amygdala activity, thereby speeding response the next go around. They’re great defenders for real and present dangers; they’re troublesome for recovery from ingrained prejudice or past trauma (e.g., PTSD).

Hormones affect our perceptions and behaviors. For example, testosterone has been correlated with confidence, optimism, and aggression while decreasing fear and anxiety.

Neuropeptides (oxytocin and vasopressin) promote pair bonding and stimulate paternal/maternal behavior. While they elicit charitable behavior toward other members of our group, they increase aggression toward strangers when protecting loved ones.

The dopaminergic system regulates the pleasure center. In a healthy individual, it confers a sense of satisfaction in goal-directed behavior that anticipates future reward. Unfortunately, over-to-top sources of reward (e.g., sugar, alcohol, drugs, gambling) engender cravings, addiction, and habituation. The more we take in, the more we want.

The frontal cortex provides cognition, working memory, emotional regulation, rational decision making, and long-term planning. It’s the area of the brain that is least influenced by genetic inheritance and most sculpted by experience. It has the capacity to interpret sensory and emotional inputs and modulate our responses. For example, amygdaloidal neurons may fire in response to perceived threat, but the frontal cortex has veto power if it thinks the stimulus isn’t scary. That being said, the amygdala tends to carry the day for split second decision making; the frontal cortex requires deliberation.

As cognitive load on the frontal cortex increases, people become less empathetic, charitable, and honest. They’re more likely to succumb to temptation or make rash decisions. Habit formation proves an effective counterweight. It reduces cognitive load by rendering behaviors automatic. Other tactics for avoiding temptation include distraction (drawing one’s mind away from the stimulus) and reappraisal (changing the narrative of what’s happening in the moment). By contrast, good old fashioned willpower increases cognitive load.

Finally, culture exerts a profound impact on how we think and behave. Collectivist cultures emphasize harmony, interdependence, and conformity; individualist cultures stress autonomy, personal achievement, and individual rights. Stratified cultures (e.g., unequal incomes) foster more violence and less trust and kindness. Urban dwellers tend to have more reactive amygdalas, causing heightened fear and anxiety.

The biology of US versus THEM struck me as one of the more fascinating topics in Dr. Sapolsky’s book. We are biologically wired to process differences in race, ethnicity, gender, social status, and beauty. Our brains are especially attuned to skin color. We form US-THEM dichotomies within milliseconds of exposure to other human beings. Dress, ornamentation, and regional accent augment the visual cues as markers of values, beliefs, and ideologies. We feel a sense of obligation and reciprocity toward those we deem part of US, and we’re more likely make amends to those within our group. THEY can be viewed as threatening, angry, and untrustworthy. THEY might even evoke disgust.

We all belong to several US-THEM groupings, and our affiliations vary over time. Yet we do not need to be held hostage to our biological or cultural biases. If we acknowledge that factions exist, we can choose to follow our better angels. We can focus on larger, shared goals. We can invest the time and effort to “walk in someone else’s shoes” and see the world from a different vantage point. And we can stop, question, think, and reason when confronting engrained biases.

It takes more cognitive load to empathize with people with whom there is less common ground. Social competency demands more processing cycles in the frontal cortex. Yet sustained contact among groups decreases prejudice while increasing knowledge and empathy.

The good news: We make neurons throughout our lives, and our neurons regularly remap. So even old dogs can learn new tricks!

I used to think that our brains were like computers. After all, they process lots of input, use logic to make executive decisions, store and retrieve memories, and produce output. Yet after reading Welcome to Your Brain and watching Dr. Sam Wang’s 36-part DVD entitled Neuroscience of Everyday Life, I have a whole new perspective.

Our brains are not designed for pinpoint accuracy, like a computer. They’re in the business of keeping us alive. To that end, Dr. Wang tells us that “at any given moment, your brain is lying to you.” Here’s how…

The brain takes in huge amounts of information through its sensory processors – eyes, ears, nose, mouth, and skin. As it sifts through the input, it uses a lifetime of experience and its  contextually-based expectations to interpret the raw data and then decide what will be processed and retained and what will be discarded. Speed takes precedence over accuracy.

Forty percent of our brain is sensitive to visual stimulation. A large number of brain regions can activate in response to visual signals without entering that input into consciousness. Conscious awareness may function like a spotlight that focuses on specific stimuli and ignores others. And by the time we’re cognizant of visual images, our brains have already made assumptions about what we’re looking at.

The brain’s mechanism for storing and retrieving memories also falls into the realm of not-at-all-like-a-computer. Memories get stored in shorthand based on what the brain considers important. There’s also good evidence that we erase and re-write our memories every time we recall them. And we invent details to fill in the gaps and create a more coherent story. Researchers have demonstrated this phenomenon in laboratory experiments. For example, they can show their subjects a list of words that share a consistent meaning – e.g., ice cream, honey, lollipop, sugar, candy, chocolate. When asked later if the word sweet was on the list, most folks say yes with confidence. They make a reasonable inference that the word made the list even though it did not.

The hippocampus serves as the initial repository for our memories. In the process of rewriting as we re-experience them, memories can transition from the hippocampus to the neocortex. As this transfer occurs, some memories get separated from the context in which they occurred and get woven into the fabric of our general knowledge. For example, we’ll remember that Salem is the capital of Oregon, but we won’t recall when, where, or how we learned that fact. Dreams likely play an important role in memory consolidation.

Armed with this information, I’m more likely to adopt a generous response when others recount memories that are inconsistent with my recollection. I’ll also be wary of declaring that my historical narratives are factually true.

Our brains also play close attention to activity on all of its synaptic connections. It strengthens synapses that see frequent use (“cells that fire together, wire together”). This mechanism enables us to execute thousands of sequences in everyday life without having to think much about them (e.g., tying our shoe laces). It also weakens or removes synapses that remain dormant while others are actively used (“out of synch, lose you link”). This phenomenon is referred to as neural plasticity. It has several important practical applications:

• If there’s a goal that you’d like to accomplish, visualize the process of attaining it in as much detail as possible and as often as possible. When your brain is wired for success, you’re far less likely to be stymied by roadblocks along the way.
• When teaching a class, provide some initial exposure to key facts or conclusions. By preparing the brain for what’s ahead, it’s more likely to pay attention to specific pieces of information. For example, an early quiz sets the brain up for future learning.
• If you need to study for an exam, break your preparation into several relatively small sessions (45-90 minutes). Your brain will retain information longer if it has the chance to process it between study sessions.
• If something or someone makes you unhappy, find a way to distract yourself when the memory emerges. If you dwell on it, you simply reinforce the pain and increase the likelihood that it will keep popping up. Turn your attention to something pleasant.
• Reappraisal is a powerful tool for transforming unhappy memories. Find a way to change the meaning of the event into something positive and forwarding. Folks skilled in reappraisal tend to be emotionally stable and resilient.

Finally, frequent small positive events have a greater cumulative effect on happiness than large positive events. For example, when people win the lottery, they typically go through an initial period of euphoria after which they revert to their former set points. To elevate your set point, eliminate daily irritants, set realistic goals and achieve them, use your character strengths, and cultivate a daily practice of gratitude.